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As an addendum to the above from Kevin, 2014 allows you to update/insert into tables that have column store indexes on them without having to drop the index and rebuild it (or swap a partition out of the table, drop the column store, update/insert the rows, add the column store back to the partition and then swap it back to it's initial table - a lot of work to get around the only glaring limitation to column store indexes). You can also cluster on the column store index in 2014. This is especially useful if you have a data warehouse/environment that has late arriving data - not terribly useful in your case, it sounds like.

Going from SQL 2008, though, note the advantages start in SQL 2012. SQL 2012 features additional syntax compliant with ANSI SQL:2008 standard. Notable ones include the new windowing functions. Improvements to the engine and column-store as well as Always-On availability make 2012 a nice upgrade. Therefore, going to 2014 is an additive improvement.

Kevin

P.S. I agree that you should not be considering SQL 2014 if you upgrading right now. If you want immediate enhancements go to 2012. If you can wait, I would hold off until service pack 1 - or at least the RTM.